11: Evolution Flashcards
Variation definition
Variation is the differences between members of the same species
Mutation definition
A mutation is a change in DNA
Biodiversity definition and is it commonly known as?
Biodiversity is all the different species of living organisms on earth.
Biological diversity is more commonly know as biodiversity.
Evolution definition and what does it mean?
Evolution is the gradual changes that occur in species over many generations.
Evolution means gradual change occurring
What does biological diversity always involve
Biological diversity always involves DNA
What is small-scale and large-scale evolution?
Small-scale evolution will involve changes through few generations but no new species will develop e.g. the peppered moth
Large-scale evolution involves change that will cause new species over many generations e.g. over a period of about 60 million years, fossil evidence shows us modern horse evolved from a terrier-sized animal
The peppered moth and mutated version information
What is this an example of?
It is found in England, and it is a moth that flies at night but settles on trees during the day. It camouflaged on the lichens on trees and birds can’t pick off the moths easily. It is better adapted to its environment and survives in greater numbers and passes its favourable colour trait on to its offspring.
There is another form of the species that, due to a mutation, is black in colour. It is obvious against lichens on trees and is easily picked off by birds. The black version of the moth isn’t well-adapted to its environment. It is eaten by birds and doesn’t get a chance to breed and is rare because of this. This is an example of natural selection.
What happened during the industrial revolution
Lichens died on trees and the bark of trees turned black from the soot coming fron the chimneys of factories. The light coloured moths couldn’t blend in and became more obvious to birds while the black coloured moths blended in. They then lived longe out to breed and pass their genes for black color on to their offspring.
The clean air act was introduced in England and things reverted back to their old ways. Black moths will eventually become extinct very soon.
Why does extinction usually occur?
Extinction usually occurs as a result of changes to the environment/habitat of the species making it unsuitable for their survival.
Who was Charles Darwin?
What did he say?
Charles Darwin was an English naturalist who spent his entire adult life watching abd studying various species of organisms trying to work out how they came to be as they were.
He said that all living organisms had a common ancestor and that they didn’t follow a straight line of descent but that they were numerous branches in the tree of life.
What was Charles Darwin known for
Darwin is well known for his travels kn the HMS beagle and for his amazing work in the Galapagos Islands off the coast of Ecuador where he studied 23 different types of finches on the different islands. The main difference we’re in the shape or the birds beaks
What is natural selection also called
Survival of the fittest
What is important to remember about variation
Only variation caused by changes in genes can be passed on to offspring
What will individuals who are genetically adapted to their environment do?
They will survive to breed and pass those genes on to their offspring who, in turn, will survive and pass the genes on to their offspring
What will individuals who are not well adapted to their environment do?
They will not likely survive and pass their genes on to the next generation
